Split cap for woodworking-machines.



G. HELBING, JR. SPLIT GAP FOR WOODWORKING MACHINES.

APPLICATION FILED MAY 14, 1909.

95 3,203. Patented Mar.29, 1910.

CHARLES HELBING', .13., OF SAN FRANCISCO, CALIFORNIA.

SPLIT CAP FOR WOODWORKING-MACHINES.

Specification of Letters Patent.

Application filed May 14, 1909.

Patented Mar. 29, 1910.

Serial No. 496,072.

ing-Machines, of which the following is a specification in such full and clear terms as will enable those skilled in the art to construct and use the same.

This invention relates to a device used on woodworking machines to secure the cutting blades to the -revoluble heads thereof.

It is common on stickers and other kinds of planing machines to secure a knife'oi' set of knives to the revoluble head by means of a flat cap having a hole theretlniough, the cap having a bolt passed through it which is secured in a groove in the revoluble head. In order that the knives may not strike the wood being cut at the same instant across the entire knife blade it is common to give the knife what is called a shear by twisting the material of which the knife is made so that the cutting edge will strike the wood in such a manner as to cut the same at one place before another, thus preventing the wood from tearing up and leaving the finished stock rougher than it was in the first place. It also becomes necessary to make other changes in the positions of the blades used, as will be explained later, and to do this the blade itself must be prepared for special work and is of no value for any other work, a great disadvantage, since it is sometimes necessary to have on hand a very large number of blades to do a number of different classes of work.

This invention seeks to avoid the change in the shape of the blade itself, and change the location of the blade with respect to the revoluble head whereby all the five different classes of cuts may be made, and the blades may be interchanged for different kinds of work as may be desired.

In the drawings, in which the same numeral of reference is applied to the same portion throughout the several views, Figure 1 is an end View of a revoluble head showing the split cap as used when the blade is to assume the ordinary position, Fig. 2 shows the same kind of a view with the cap turned around and the knife so placed as to give the blade a shear cut from one edge, Fig. 3 shows the cap turned so the blade will be given a shear cut from the opposite end,

these two positions are very frequently used together in order to shear the shaving off the wood at two different angles thus avoiding tearing the wood as much as possible, one blade on one side of the head being used with one shear and the like blade on the opposite side being used with the opposite shear, Fig. 4; shows the blade and cap placed to give the point of the blade what is called an overreach, a very necessary thing where a deep cut is to be made, Fig. 5 shows the blade and cap arranged to give the cutting edge of the blade what is called a drag, which is used in cutting hard woods, and Fig. (5 is a plan of one of the wedges.

The cap comprises a pair of wedges 2 each of said wedges having a hole through the center thereof whereby the cap may be secured to a planer head 4 by means of bolts 3 the heads of which are placed in grooves 5 in the planer head. It will also be understood that in practice the planer head is balanced by having the same number of knives 6 placed on each side thereof, each knife of a pair being of the same weight.

It will be noted that the knife 6 is shown in Fig. 1 as extending parallel with the face of the planer head. This is the common way which such knives are used, and for some work it is necessary to so place said knife. It will be noted that both wedges are placed on the top of the knife in this figure, the object of the double wedges being to provide 'a perfectly fair bearing for the nut 7 on the bolt 3.

Fig. 2 shows the knife arranged so that itwill give one shear cut the knife being placed between the two wedges and having its edge depart from the surface of the head as it recedes. In Fig. 3 is shown the opposite form of shear cutting edge, the knife being placed between the two wedges and approaching the plane of the cutter head as it recedes. If these two forms of shearing cuts are used on the same piece of lumber, the resulting cut is very smooth for the reason that the angle of the cut changes with each shaving taken off and there is no liability to tearing slivers of the wood and leaving a rough surface.

In Fig. 4 is shown the arrangement of the knife when a very deep cut is .to be made. This becomes necessary in cutting gutters and the like molding which have deep channels. Because of the large shaving taken off the knife edge must be so placed as to strike the wood at different times along the edge of the cutting blade, and this is accomplished in the manner shown in said figure.

When cutting hard woods it is necessary to give the cutting edges of the knives What is called a drag, and this is accomplished by turning the Wedges around one hundred eighty degrees from the manner shown in Fig. 4, thus making the knife project in the manner shown in Fig. 5.

It will be understood that in each cap the double wedges permit the nut on the sec-uring bolt to have a fair seat on the cap and thus hold the knife securely in place. It will also be understood by those skilled in the art that the sides of the cutting blades which with the various arrangements shown have important functions in making the several cuts for which they are used, as for example it. may be desired to cut a deep narrow groove in a board. In such a case as this it is necessary to present one shearing edge to the side of the groove to make a clean cut, which is done by one of the knives. The other edge of the groove thus formed will be rough, but by setting the opposite knife in an opposite position the other edge of the groove may be made smooth as well.

What I desireto secure by Letters Patent of the United States is as follows:

1. A tool holder for woodworking machines comprising a pair of cooperating subs'tantially square flat wedges each having a hole therein near the center thereof, one or both of said Wedges being adapted to be placed above the tool to be held to secure the same to a cutter head, as set forth.

2. The combination with acutter head and a bit, of a pair of cooperating substantially square fiat wedges each having a hole therein and adapted to secure the bit to the cutter head in any one of five different angular positions with relation to said head, in one or more of which one or both of said wedges may act as a cap, as set forth.

In testimony whereof I have set my hand this 3d day of May A. D. 1909, in the presence of the two subscribed Witnesses.

CHARLES HELBING, JR.

'Witnesses:

H. BUMiss, G. 1:. TlRI-FFIN. 

